红外热像仪的空间噪声和时间噪声分析

噪声特性是衡量红外热像仪的一个重要指标。本文对热像仪的噪声来源和影响因素进行了分析,并通过实验分别计算了实测图像的空间噪声和时间噪声。实验结果表明了在实际观测过程中,图像的空间噪声通常要大于时间噪声,而且空间噪声在热像仪经过非均匀性校正之后的一段时间内会逐渐增大,而时间噪声不会有明显变化。基于时间噪声小于空间噪声且不随时间变化的特点,为红外图像中的目标检测提出了新的思路。

Analysis on spatial noise and temporal noise of IR thermal imager

Noise characteristic is an important indicator for evaluating an infrared thermal imager. The sources and influence factors of noise were analyzed,and the spatial noise and temporal noise of the real images were calculated through the experiment. The results show that the spatial noise is usually greater than the temporal noise,and the spatial noise gradually increases after nonuniform correction of infrared thermal imager,while temporal noise has no obvious change. This characteristic provides new thoughts for target detection in infrared images.